Got a jump after car wouldn’t start and it worked fine. Tried it once home about 15 mins. Later and nothing. Another jump, drove for 30 mins fine, next morning, nothing. Auto store ran voltmeter which said battery and alternator were supposedly working fine. Filled water reservoir in battery which was low, drove 40 mins. Now three hours later, nothing! 2003 kia rio. Ideas?
If That’s The Original Battery Then It’s 8 To 9 Years-Old. Get It Out Of There !Time For A New One And Then Go From There.
Once a battery has been discharged it should be charged back up using a battery charger.
If you haven’t cleaned the battery connections already then do that. It sounds like the alternator isn’t getting charge to the battery for some reason. Measuring the voltage between the output lead of the alternator and the positive battery post should show no more than about .3 volts if things are good.
This could just be the battery connections. The alternator can’t get a charge to go into the battery and the charge in the battery can’t get out to the starter. A voltmeter test done by the autoparts store is not a definitive test of the condition of either the battery or the alternator. The battery needs to be taken out and load tested, not just a voltage test.
But you’ve had it tested…and it’s tested fine…I suspect it’s the battery connections…